# External validation of the REDUCTION clinical decision aids for ruling out fractures in patients with midfacial and mandibular injuries in the emergency department: a protocol for a prospective multi-centre cohort study

## TL;DR

This study aims to validate clinical decision tools that could reduce unnecessary CT scans for facial and jaw injuries in emergency departments.

## Contribution

The study introduces and externally validates clinical decision aids to safely rule out fractures and reduce CT use in facial injury cases.

## Key findings

- The diagnostic accuracy of the decision aids will be evaluated using sensitivity, specificity, and negative predictive value.
- The study will determine if the aids can safely reduce unnecessary CT scans in patients with midfacial or mandibular injuries.

## Abstract

Computed Tomography (CT) is the gold standard for diagnosing midfacial and mandibular fractures in emergency department (ED) patients. However, its increasing availability has led to more frequent use, resulting in higher healthcare costs and unnecessary radiation exposure. Although various clinical parameters can assist in diagnosis of maxillofacial fractures, none are reliable enough to rule them out individually. To support clinical decision-making, and to reduce unnecessary imaging, the REDUCTION studies developed four decision aids based on combinations of clinical parameters. The aim is to rule out: (I) midfacial fractures, (II) midfacial fractures requiring active treatment, (III) mandibular fractures, and (IV) mandibular fractures requiring active treatment. Before being implemented, these aids must undergo external validation.

A prospective multi-centre validation study will be conducted in six hospitals in the Netherlands. Patients presenting at the ED with midfacial and/or mandibular injury will undergo a standardized physical examination based on the parameters included in the decision aids. The X-ray images will be reviewed to assess for fractures, and electronic patient records will be analyzed to determine whether fracture treatment was active or conservative. The diagnostic accuracy of each decision aid will be determined by calculating their sensitivity, specificity, and negative predictive value.

The REDUCTION validation trial will assess whether the developed clinical decision aids can be used safely to reduce unnecessary CT scans in patients with midfacial or mandibular injuries at the ED. If accurate, these decision aids could be integrated into emergency care to support decision-making, leading to fewer CT scans, lower radiation exposure, reduced healthcare costs, and safe, efficient management of maxillofacial injury.

ICTRP: NL-OMON56277.